<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Flex Layout</title>
    <style>
        .verticalLayout {
            display: flex;
            flex-direction: column;
            height: 100px;
            border: 1px solid #ccc;
            color: white;
        }

        .vlItem01 {
            background-color: seagreen;
            height: 32px;
        }

        .vlItem02 {
            background-color: tan;
            flex: 1;
        }

        .vlItem03 {
            background-color: tomato;
        }

        .container {
            margin-top: 5px;
            height: 256px;
            border: 1px solid #ccc;
        }

        .container>div {
            height: 100%;
        }
    </style>
</head>

<body>
    <div class='verticalLayout'>
        <div class='vlItem01'>Block One</div>
        <div class='vlItem02'>Block TWO</div>
        <div class='vlItem03'>Block THREE</div>
    </div>
    <div class='container'>
        <div class='verticalLayout'>
            <div class='vlItem01'>Block One</div>
            <div class='vlItem02'>Block TWO</div>
            <div class='vlItem03'>Block THREE</div>
        </div>
    </div>
</body>
<script defer="true" type="text/javascript">

</script>

</html>